"Mayer provides a crucial analysis of the ways in which inquisitorial activities could fit into the political agenda of the popes and illuminates both the power and limits of the inquisitions as papal tools in the context of Italian political rivalries. As with his first volume, this work will be essential to anyone seeking a fuller understanding of the Roman inquisition at the turn of the seventeenth century."—Jonathan Seitz, American Historical Review

"An extremely important project. Mayer brings an unprecedented amount of archival research to the table, and his findings will be epoch-making and definitive."—Henry Ansgar Kelly, University of California, Los Angeles

"A profoundly researched analysis of how the Sacred Congregation of the Roman Inquisition actually operated at the center, its procedures, developed 'style,' and jurisprudence as revealed by congregational registers, inquisitors' manuals, and apt sample cases. We learn of the personnel involved, from Cardinal Inquisitors to consultants and notaries. Mayer is especially revealing about some involved in judging Galileo's books and behavior."—Christopher Black, University of Glasgow

While the Spanish Inquisition has laid the greatest claim to both scholarly attention and the popular imagination, the Roman Inquisition, established in 1542 and a key instrument of papal authority, was more powerful, important, and long-lived. Founded by Paul III and originally aimed to eradicate Protestant heresy, it followed medieval antecedents but went beyond them by becoming a highly articulated centralized organ directly dependent on the pope. By the late sixteenth century the Roman Inquisition had developed its own distinctive procedures, legal process, and personnel, the congregation of cardinals and a professional staff. Its legal process grew out of the technique of inquisitio formulated by Innocent III in the early thirteenth century, it became the most precocious papal bureaucracy on the road to the first "absolutist" state.

As Thomas F. Mayer demonstrates, the Inquisition underwent constant modification as it expanded. The new institution modeled its case management and other procedures on those of another medieval ancestor, the Roman supreme court, the Rota. With unparalleled attention to archival sources and detail, Mayer portrays a highly articulated corporate bureaucracy with the pope at its head. He profiles the Cardinal Inquisitors, including those who would play a major role in Galileo's trials, and details their social and geographical origins, their education, economic status, earlier careers in the Church, and networks of patronage. At the point this study ends, circa 1640, Pope Urban VIII had made the Roman Inquisition his personal instrument and dominated it to a degree none of his predecessors had approached.

Thomas F. Mayer is Professor of History at Augustana College. He is author of Reginald Pole: Prince and Prophet, and editor and translator of The Trial of Galileo, 1612-1633.